Work

Bcl-2 Inhibits a Fas-induced Conformational Change in the Bax N Terminus and Bax Mitochondrial Translocation

Year: 2000

Type: article

Abstract: Members of the Bcl-2 family of proteins control the cellular commitment to apoptosis, although their role in Fas-induced apoptosis is ill-defined. In this report we demonstrate that activation of the Fas receptor present on a human breast epithelial cell line resulted in a conformational change in the N terminus of the pro-apoptotic protein Bax. This conformational change appeared to occur in the cytosol and precede Bax translocation to the mitochondria. Overexpression of the anti-apoptotic protein Bcl-2 inhibited both the conformational change of Bax as well as its relocalization to the mitochondria. Bcl-2 overexpression did not, however, inhibit Fas-induced cleavage of both procaspase-8 and the pro-apoptotic protein Bid, indicating that Bcl-2 functions downstream of these events. These results suggest that the mechanism by which Bcl-2 inhibits Bax mitochondrial translocation and subsequent amplification of the apoptotic cascade is not by providing a physical barrier to Bax, but rather by inhibiting an upstream event necessary for Bax conformational change.

Source: Journal of Biological Chemistry

DOI: 10.1074/jbc.c900590199

Authors: Kathleen M. Murphy, Uldis N. Streips, Richard B. Lock

Institutions: University of Louisville, Children's Cancer Institute Australia

Language: English

Topic: Cell death mechanisms and regulation

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,430